private void addModulePath(PyFile followed) {
   // what to prepend to a module description?
   final VirtualFile file = followed.getVirtualFile();
   if (file == null) {
     myProlog.addWith(TagSmall, $(PyBundle.message("QDOC.module.path.unknown")));
   } else {
     final String path = file.getPath();
     RootFinder finder = new RootFinder(path);
     RootVisitorHost.visitRoots(followed, finder);
     final String rootPath = finder.getResult();
     if (rootPath != null) {
       String afterPart = path.substring(rootPath.length());
       myProlog.addWith(TagSmall, $(rootPath).addWith(TagBold, $(afterPart)));
     } else {
       myProlog.addWith(TagSmall, $(path));
     }
   }
 }